A liquid filling type pressure sensor in which a semiconductor type pressure detection device is accommodated inside a pressure receiving chamber partitioned by a diaphragm to be filled with oil has been used to detect a refrigerant pressure by being installed in a refrigerator-freezer or an air conditioner, or to detect a pressure of supplied oil by being installed in a fuel feeder of a vehicle.
The semiconductor type pressure detection device is disposed inside the pressure receiving chamber, and has a function of converting a pressure change inside a pressure receiving space into an electric signal and outputting the converted electric signal to the outside through a relay board or a lead wire.
Referring to such a pressure sensor, liquid such as water may enter the sensor from the outside to cause a defect in the semiconductor type pressure detection device depending on an environment in which the pressure sensor is installed or a usage condition of the device.
In this regard, there has been a known pressure sensor in which a cover is attached to a base accommodating a semiconductor type pressure detection device to fill the inside of the cover with an adhesive, thereby enhancing water tightness (see Patent Document 1).